青藏高原城镇化格局的时空分异特征及影响因素

研究青藏高原城镇化格局的时空分异及其影响因素,有利于推动青藏高原现代人类活动时空过程的认知,对青藏高原就地就近城镇化及可持续发展具有参考意义。根据历次人口普查数据,本研究构建青藏高原县市尺度城镇化空间数据集,参考城镇化发展阶段,采用LISA空间类型划分法和空间计量回归模型,系统分析1990-2010年青藏高原内部城镇化格局的时空分异特征及影响因素。主要结论包括：① 青藏高原整体城镇化水平偏低,2017年底,青藏高原主体部分青海省和西藏自治区的常住人口城镇化水平分别为53.07%和30.8%,低于全国同期水平的58.52%,但青藏高原内不乏高水平城镇化地区,而且各地区间城镇化水平的空间差异缩小;② 青海西部柴达木盆地是高水平城镇化集聚区,羌塘地区是低水平城镇化集聚区,地级行政中心所在县市多呈现自身高、周边低的城镇化格局;③ 与内地相似,第二、三产业从业机会是推动青藏高原城镇化发展重要因素,社会公共服务资源对城镇化拉动作用开始凸显。研究结果可以为青藏高原人类活动研究和青藏高原就地就近城镇化可持续发展政策提供参考。

Spatio-temporal Pattern and Drivers of the Population Urbanization in the Tibetan Plateau

Although the Tibetan Plateau has the lowest level of urbanization in China, it has experienced a significant urbanization development since the "Opening-Up and Reform" in 1978. Based on China's population census data in 1990, 2000, and 2010, this paper constructed a county-level spatial database of population urbanization for the Tibet Autonomous Region and Qinghai Province. Using the methods of urbanization stage classification, LISA types classification, and spatial regression models, this study analyzed the spatiotemporal dynamics and driving factors of the population urbanization in the Tibetan Plateau from 1990 to 2010. The main results are as follows. (1) Overall, the Tibetan Plateau had relatively low urbanization, with the level being 22.03%, 28.11%, and 37.05% in 1990, 2000, and 2010 respectively. However, some counties/cities had high urbanization level, including Xining (provincial capital of Qinghai Province), Lhasa (provincial capital of Tibet Autonomous Region), and some mining cities. The urbanization level of these cities/counties could reach even 100%. Most counties in the Tibetan Plateau remained still at the low-level urbanization stage. In addition, the spatial difference of population urbanization in the Tibetan Plateau changed gradually from 1990 to 2010. (2) The Qaidam Basin in western Qinghai Province was the main cluster of high-level urbanization areas, while the Qiangtang area in western Tibet was the largest cluster of low-level urbanization areas. The former had many mining cities while the latter was famous for inhospitable ecological environment and low population density. When compared to neighboring counties/cities, the prefecture-level capitals usually had higher urbanization, which formed a core-periphery pattern of urbanization. (3) Similar to most places in China, off-farm job opportunity, in the secondary industry and tertiary industry, was one of the key drivers of the urbanization in the Tibetan Plateau. Social public service resources also promoted urbanization development. More and more population migrated into urban areas in the Tibetan Plateau due to urban socioeconomic developments. Natural factors were not the significant factors for the spatial difference of population urbanization in the Tibetan Plateau. In some cities or towns, however, natural factors such as topography, had a constraining role for urban growth. The urbanization level in pastoral areas usually lagged behind. In the future, more attention should be paid on the sustainable development of the mining cities and towns in the Tibetan Plateau. Based on the "Belt and Road Initiative", the border cities and towns should be highlighted as not only frontiers but also trading hubs. Moreover, ecomigrants could be encouraged to move into new homes in cities and towns. This paper is hopefully beneficial for future studies of the human activities and sustainable urbanization policy-making in the Tibetan Plateau.